Bearing System and Gear Unit

ABSTRACT

A bearing system having a housing component, a shaft being supported in the housing component with the aid of a bearing, especially using a roller bearing, wherein the bearing is accommodated in a stepped bore in the housing component, which especially extends through the housing component, a lid part seals the stepped bore, especially with respect to the outside, the lid part is frictionally connected to the housing component, the lid part is accommodated in the stepped bore, a surface section of the outside of the lid part is situated in alignment with a step of the stepped bore, in particular in such a way that the surface section is situated on an axial position of the step.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 14/766,345, filed on Aug. 6, 2015, which is the national stageentry of International Application No. PCT/EP2014/000235, filed on Jan.29, 2014, which claims priority to German Patent Application No. 10 2013002 050.6, filed on Feb. 7, 2013, each of which is incorporated hereinin its entirety by reference thereto.

FIELD OF THE INVENTION

The present invention relates to a bearing system and a gear unit.

BACKGROUND INFORMATION

German Published Patent Application No. 10 2007 058 918 illustrates agear unit having a bearing system.

SUMMARY

Therefore, the invention is based on the objective of further developinga bearing system and a gear unit with a view toward better environmentalprotection.

Important features of the present invention in the bearing systemincluding a housing component, in which a shaft is supported with theaid of a bearing in the bearing component, especially using a rollerbearing, are that the bearing is accommodated in a stepped bore in thehousing component, which in particular extends through the housingcomponent, a lid part seals the stepped bore, especially with respect tothe outside, the lid part is frictionally connected to the housingcomponent, the lid part is accommodated in the stepped bore, a surfacesection of the outside of the lid part is situated in alignment with astep of the stepped bore, in particular so that the surface section issituated on an axial position of the step.

This has the advantage that the bearing system in the housing componentis able to be insulated from the environment with the aid of the lidpart. The bearing system is therefore protectable from penetrating dirtparticles, and the operational reliability can be improved.

The frictional connection of the lid part to the housing component isable to be established in an uncomplicated manner, so that the bearingsystem can be produced cost-effectively.

The lid part makes it possible to realize the bearing system in anoil-tight manner. The bearing system may therefore be used even inapplication fields that set high hygienic standards.

The surface section of the lid part is advantageously situated inalignment with the step. As a result, the surface section and the stepdefine a plane, so that the housing component having the lid part iseasy to clean.

In one advantageous development, the inner diameter, especially theinside diameter, of the stepped bore decreases monotonously in the boredirection, i.e., the axial direction, and therefore in particular in thedirection of the shaft axis. This has the advantage that the lid part iseasily able to be introduced into the stepped bore. A cost-effectiveinstallation is possible as a result.

The inner diameter of the bore advantageously decreases in the directionof the bearing.

In one advantageous development, the stepped bore has a step with abevel. This is advantageous insofar as the step can be used as a stopfor an installation tool for the lid part. The bevel facilitates thepositioning of the lid part inside the stepped bore.

In one advantageous development, the axial position of the surfacesection is the axial position of the lid part that lies farthest fromthe bearing. This is advantageous insofar as the lid part is able to beintroduced into the stepped bore with the aid of a conventional punchingtool and be aligned in a flush manner with the step in the stepped bore.The punching tool has a circular planar punching surface having adiameter that is essentially identical with the maximum diameter of thestepped bore. As a result, the lid part is able to be pressed evenlyinto the stepped bore with the aid of the punching tool. Tilting of thelid part in the stepped bore is able to be prevented, so that thetightness of the connection between the lid part and the housingcomponent is able to be improved.

In one advantageous development, a retaining ring is situated axiallybetween the bearing and the lid part in a radially aligned annulargroove of the stepped bore. This is advantageous insofar as theretaining ring delimits the bearing in the axial direction, so that thelid part is able to be spaced apart from the bearing. The reliability ofthe bearing system is therefore improved.

In one advantageous development, the retaining ring is set apart fromthe lid part. This is advantageous insofar as the risk of aninstallation error is able to be reduced. The spacing acts as tolerancerange, so that in a deviation of the position of the lid part inside thestepped bore, a deformation of the lid part within this tolerance rangeis able to be prevented. This reduces the risk of an oil leak at the lidpart and thus improves the operational reliability.

In one advantageous development, a spacer ring is axially situatedbetween the retaining ring and an outer ring of the bearing, theretaining ring together with the spacer in particular delimiting theouter ring of the bearing in the axial direction. This has the advantagethat an axial force acting on the bearing via the shaft is able to beabsorbed by the spacer and the retaining ring. The spacer and theretaining ring therefore make it possible to delimit the shaft and thebearing in the axial direction.

In one advantageous development, the lid part is developed in the formof a cup, which advantageously allows the lid part to be produced in anuncomplicated manner. For example, the lid part is able to be producedas a punched and bent part.

In one advantageous embodiment, the lid part has a base section and awall section. This is advantageous insofar as the wall section may beused for sealing the bearing system from the housing section. The shaftend is able to be covered by the base section.

In one advantageous development, the wall thickness of the wall sectionincreases monotonously toward the base section. This has the advantagethat an end region of the wall section facing away from the base sectioncan be designed to be elastically deflectable. This makes it possible toimprove the tightness of the connection between the lid part and thehousing component.

In one advantageous development, the outer radius of the wall sectionincreases linearly toward the base section in an axial end region facingthe bearing, in particular. This has the advantage that a bevel is ableto be realized on the end region, which simplifies the introduction ofthe lid part into the stepped bore.

In one advantageous development, the inner radius of the wall sectionbecomes larger in a stepwise manner. This has the advantage that thestability of the wall section increases toward the base section. An endregion of the wall section facing away from the bottom section thus isable to have greater elasticity than an end region of the wall sectionfacing the bottom section. This simplifies the introduction of the lidpart into the stepped bore and simultaneously makes it possible toachieve a reliable connection between the lid part and the housingcomponent.

In one advantageous development, the lid part is developed as asheet-metal part, especially a steel part, especially as a punched andbent part, the sheet-metal part being at least partially plastic-coated.This has the advantage that the lid part can be produced in anuncomplicated and cost-effective manner. The low wall thickness ofsheet-metal parts, which in particular is less than 3 mm, facilitatesthe elastic deformability of the wall section, so that the installationof the lid part becomes easier.

In one advantageous development, the plastic is an elastomer. This isadvantageous insofar as the elastomer makes it possible to protect thesheet-metal part of the lid part from damage, which increases theperformance reliability.

In one advantageous development, the plastic coating is also situatedradially between the sheet-metal part and the housing component, theplastic coating being elastically deformed, in particular so that theplastic coating seals the sheet-metal part with respect to the housingcomponent. This has the advantage that an additional sealing means maybe omitted, which makes it possible to reduce the production expense.

In one advantageous development, the radius of the shaft decreases in astepwise manner in the direction of the bearing, a step in the shaft inparticular being set apart from an inner ring of the bearing; themaximum outer radius of the shaft is greater than an inner radius of theinner ring, and a bushing is situated on the shaft. This has theadvantage that axial forces acting on a toothed wheel situated on theshaft are transmittable to the bearing with the aid of the bushing, sothat the loading of the shaft is able to be reduced. In particular theloading of the step developed on the shaft is able to be relieved, sothat a breakout of the shaft is preventable. The operational reliabilityof the bearing system can therefore be improved.

In one advantageous development, the bushing touches the inner ring.This has the advantage that forces axially acting on the bushing aretransmitted directly to the inner ring of the bearing with the aid ofthe bushing. This relieves the stress on the shaft.

In one advantageous development, an inner diameter of the bushing isgreater than the inner diameter of the inner ring, the outer diameter ofthe bushing in particular being smaller than the outer diameter of theinner ring. This has the advantage that a force axially acting on thebushing is transmittable to the inner ring in its entirety. The completeradial surface of the bushing advantageously touches the inner ring, sothat a reliable force transmission is able to be realized.

In one advantageous development, the bushing is situated axially betweena toothed wheel connected to the shaft, and the inner ring. This has theadvantage that axial forces and/or forces including an axial component,which are acting on the toothed wheel, are able to be shifted toward thebearing with the aid of the bushing. The loading of the shaft istherefore able to be reduced and the operational reliability improved.

In one advantageous development, at least one rolling element issituated between the inner ring and the outer ring of the bearing. Thisis advantageous insofar as a roller bearing provided with rollingelements is exposed to only minor rolling friction.

Important features of the present invention in the gear unit including abearing system are that a housing of the gear unit encloses all toothedelements of the gear unit and accommodates the bearings of the gearunit,

the housing having a frame section and a cladding section, the framesection and the cladding section in particular being developed in onepiece and/or being connected in an integral fashion, the frame sectionhaving a greater wall thickness than the cladding section, the framesection having two outer leg sections and a center leg section.

This is advantageous insofar as the housing is able to be reinforcedwith the aid of the frame section. The toothed elements disposed insidethe housing are protectable by the cladding section. This makes itpossible to reduce the weight of the housing. A lightweight gear unitcan be produced in a cost-effective manner because the material expenseis able to be lowered. In addition, the ability to transport andposition the gear unit can be improved, which also results in betterenvironmental protection because material and energy are able to besaved.

In one advantageous development, each outer leg section is disposed at anonvanishing angle with respect to the center leg section, the outer legsections and the center leg section being situated in a U-shape, inparticular. This has the advantage that the reinforcing frame sectionextends across three sides of the housing. The torsional stiffness ofthe housing is therefore able to be improved.

In one advantageous development, at least one outer leg section has atleast one annular section, the annular section in particular beingdeveloped in one piece with the outer leg section. This has theadvantage that a bearing for support of a shaft of the gear unit can beaccommodated in the annular section. Forces acting on the bearing aretherefore able to be absorbed by the outer leg section.

In one advantageous development, the center leg section includes asupport section, the support section in particular being developed inone piece with the center leg section. This is advantageous insofar asthe housing is able to be supported with the aid of the support section.The integral development of the support section with the center legsection is especially advantageous because a firm connection between thesupport section and the center leg section is able to be realized. Therisk that the support section breaks away from the center leg section isreducible, which increases the performance reliability.

In one advantageous development, a ring is connected to the annularsection, especially in a releasable manner, the ring in particular beingscrewed into the annular section, and the housing is situated on abracket element so as to be at least partially supported, the bracketelement having a depression, especially on its upper side, in order toaccommodate the ring, the bracket element forming a seat for the ring,in particular. This has the advantage that the housing is able to reston the bracket element. The bracket element may have a vibration-dampingdesign, so that the housing is able to positioned in a vibration-dampedmanner. This makes it possible to extend the service life of the gearunit.

The ring is advantageously able to be mounted on different annularsegments in an uncomplicated manner. The position of the bracket elementthus is easily adaptable to the application. The number of componentscan be reduced and the environment protection be improved.

In one advantageous development, a partial ring, especially a half ring,is connected to the bracket element, especially by means of screws. Thishas the advantage that the ring can be attached to the bracket elementwith the aid of the partial ring. The bracket element can thereforeabsorb the weight force of the gear unit as well as torsional forcesacting on the gear unit.

In one advantageous development, the ring is retained in a keyedconnection between the partial ring and the bracket element, especiallyinterposed and/or clamped. This is advantageous insofar as the ring isable to be fixed in place on the bracket element over a large surfaceand thus in a reliable manner.

In one advantageous development, a plane is defined by the outer legsections and the center leg section, the plane in particular beingaligned horizontally and/or essentially in parallel with respect to abase surface of the housing. This has the advantage that the mass of thehousing, which is primarily concentrated in the frame section, is evenlydistributable in the horizontal direction. As a result, the torsionalstiffness of the housing is able to be improved even further.

In one advantageous development, the wall thickness of the frame sectionis greater than in any other region of the housing. This has theadvantage that the stiffness of the housing is improvable, while themass of the housing is able to be reduced at the same time, so thatsavings in material are possible.

In one advantageous development, at least one annular section of eachouter leg section has at least one bearing seat in each case, in which abearing is accommodated in order to support at least one shaft of thegear unit. This has the advantage that the bearing seats are able to beimplemented in a stable and secure manner by the annular sections.Forces acting on the bearings and thus the bearing seats by the shaftssupported in the bearings are able to be absorbed by the frame section,which makes it possible to improve the operational reliability of thegear unit.

In one advantageous development, an output shaft of the gear unit issupported in annular sections of the outer leg sections with the aid ofbearings. This is advantageous insofar as the output shaft, whichtransmits the torque to the application connected to it, is able to besupported in a secure manner. Even forces that are transmitted from theapplication to the output shaft are absorbable with the aid of the framesection.

In one advantageous development, the support section overhangs thecenter leg section, in particular as an outwardly directed protuberance,and/or projects from it, the support section in particular beingdeveloped in the form of a tab on the center leg section, and thesupport section being connected, especially in a releasable manner, to asupport element, in particular by a screw connection. This isadvantageous inasmuch as the support element can be used as torquesupport, so that torsional forces acting on the gear unit are able to beabsorbed by the support element. The support element may be placed on afoundation or a support structure. Moreover, the support element may beequipped with a damping element, so that the housing can be positionedin a damped manner.

In one advantageous development, the support section has a bore, thebore direction running perpendicularly to the plane spanned by the outerleg sections and the center leg section. This is advantageous inasmuchas a screw or a pin or a recessed bolt is able be guided through thebore in order to connect the support element and the support section, sothat the connection can be implemented in an uncomplicated manner. Theperpendicular alignment of the bore in particular makes it possible forthe support element to absorb transverse forces.

The bore direction is advantageously aligned in parallel with the normalvector of this plane.

In one advantageous development, a clutch housing is connected to theframe section, the outer circumference of the clutch housing taperingtoward the housing, and/or the outer diameter of the clutch housingdecreasing toward the housing, the clutch housing in particular beingimplemented in conical form and/or essentially as a cone, and a step isdeveloped in the inner diameter of the clutch housing in the directionof the housing, so that the wall thickness of the clutch housingincreases in a stepwise manner, axial bores in particular beingimplemented in the step in the circumferential direction, and screwsbeing guided through the bores in order to connect the clutch housing tothe housing. This is advantageous insofar as the clutch housing, whichaccommodates a clutch for connecting a motor shaft to the input shaft ofthe gear unit, surrounds the clutch in the form of a housing, so thatthe clutch is able to be protected from contamination. In addition, thesafety of the gear unit is able to be improved because foreign bodiesare unable to get trapped in the clutch.

In one advantageous development, a subsection of the clutch housing hasa greater wall thickness than other areas of the clutch housing. Thishas the advantage that the torsional stiffness of the clutch housing canbe improved.

In one advantageous development, a motor is connected to the housingwith the aid of the clutch housing, which has the advantage that themotor can be held by the clutch housing, so that no additional retainingdevice for the motor is needed. This results in fewer components, sothat the linkage of the motor is able to be realized in a cost-effectivemanner.

In one advantageous development, the subsection axially extends from thehousing to the motor and covers an angle range at circumference of lessthan 90° and/or is restricted in the circumferential direction. Thisadvantageously makes it possible to achieve high torsional stiffness ata reduced outlay in material.

In one advantageous development, the frame section is continued by thesubsection in the clutch housing. This is advantageous inasmuch as theclutch housing is alignable with the frame section, so that the weightforce of the motor is transmittable to the reinforced frame section anda breakaway of the thinner cladding section is preventable.

In one advantageous development, the subsection has a bore, which issealed with the aid of a sealing part, the bore in particular beingsealed in a tight and reversible manner by an inspection lid. This isadvantageous inasmuch as the clutch located inside the clutch housingcan be inspected through the inspection opening. This improves thereliability of the clutch.

In one advantageous development, an input shaft of the gear unit extendsfrom the clutch housing through the first and second outer leg sections.This has the advantage that the input shaft of the gear unit is easilyconnectible to the motor shaft at both ends of the shaft.

In one advantageous development, the input shaft is at least partiallyguided through two annular sections. This has the advantage that thebearings of the shaft are able to be placed into the annular sections,so that the gear unit may have a compact design.

In one advantageous development, an end region of the input shaft facingaway from the clutch housing is connected to a brake device. This hasthe advantage that if braking takes place, the stress on the toothedelements of the gear unit is able to be relieved since the brake deviceis connected directly to the motor via the input shaft.

In one advantageous development, the cladding section includes areinforcement segment. The extension, especially the height, of thehousing decreases monotonously from the output shaft of the gear unit tothe input shaft of the gear unit in a direction perpendicular to theaxis of the output shaft and perpendicularly to the outer leg sections,and in particular decreases linearly in a longitudinal section of thehousing parallel to an outer leg section. In particular, a normal vectorof the essentially planar reinforcement surface section stands at anonvanishing angle in relation to a normal vector of the plane definedby the outer leg sections and the center leg section. This has theadvantage that the torsional stiffness of the housing can be improvedwith the aid of the reinforcement area section. The reinforcement areasection functions as an integrated torque support for the gear unit, sothat an additional torque support can be saved and the gear unit is ableto be produced in a cost-effective manner.

Further advantages are derived from the dependent claims. The presentinvention is not restricted to the feature combination of the claims.Those skilled in the art will discover additional meaningful combinationpossibilities of claims and/or individual claim features and/or featuresof the specification and/or of the figures, that arise from the statedobjective and/or the objective resulting from a comparison with therelated art, in particular.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an oblique view of a gear unit according to the presentinvention.

FIG. 2 shows the gear unit according to the invention in a furtheroblique view.

FIG. 3 shows a sectional view of a bearing system having a lid partaccording to the invention.

FIG. 4 shows a schematic representation of a frame section of the gearunit according to the invention.

FIG. 5 shows a schematic view of a seat of the frame section.

DETAILED DESCRIPTION

The gear unit according to the present invention shown in FIGS. 1 and 2has a housing 33, in which toothed wheels and shafts (not shown) aresituated.

Housing 33 is realized in one piece or as one part and in essentiallyrectangular form and preferably produced as a cast component. Housing 33has a reinforcement surface section 1, and a plane includingreinforcement surface section 1 intersects a plane that encompasses abase area of housing 33 at a nonvanishing angle which is smaller than90°. The height of housing 33 thus decreases in linear fashion in adirection along reinforcement surface section 1. The height in the areaof an output shaft 21 is greater than the height in the area of an inputshaft. Here, the height of housing 33 is defined as the extension of thehousing perpendicularly to the direction of the shaft axis andperpendicularly to a plane that includes an input shaft and an outputshaft 21 of the gear unit.

Adjacent to reinforcement surface section 1 housing 33 has anuninterrupted recess (not shown), which is sealed by an in particularrectangular lid part 2. Lid part 2 is connected to housing 33 byfastening means 3, preferably implemented as screws, and guided throughbores in lid part 2 and screwed into tapped holes in housing 33. Therecess is large enough to introduce toothed wheels through the recessand into housing 33.

On the bottom area lying across from lid part 2 there is at least oneconnection surface having a bore (35, 36, 37, 38). A fastening means, inparticular a screw or a threaded rod, can be guided through the bore(35, 36, 37, 38) in order to connect housing 33 to a support element(not shown) or a hall floor. The connection surface is disposedessentially parallel to the floor surface for this purpose. The bore(35, 36, 37, 38) preferably extends parallel to the normal vector of theconnection surface.

Housing 33 has a surface section 34 for attaching an integrally formedthree-dimensional mark. Surface section 34 is provided with wavelikestructures for this purpose.

To connect a clutch housing to housing 33, housing 33 has a connectionsurface 39, which surrounds an uninterrupted bore for accommodating abearing part of an input shaft (not shown) of the gear unit. Connectionsurface 39 is essentially circular in a plane of housing 33, thecircular form being flattened on two sides, i.e., being partiallydeveloped in a linear fashion in circumferential direction. At least onetapped hole 24 and at least one center bore 25 are disposed inconnection surface 39, which are situated on a circular arc surroundingthe bore. The bore is sealed with the aid of a lid part 22. Lid part 22is frictionally connected to housing 33 for this purpose.

Also disposed in connection surface 39 is a second uninterrupted borefor accommodating a bearing part. Connection surface 39 thus likewisesurrounds the second bore. Toward this end, the outer contour ofconnection surface 39 deviates from the circular form in the region ofthe second bore and has a bulge. The second bore is sealed with the aidof a lid part 23. Lid part 23 is frictionally connected to housing 33for this purpose.

On the side of housing 33 situated opposite the connection surface 39there is another connection surface. The further connection surface isdeveloped essentially in mirror symmetry with connection surface 39.That is to say, it has two uninterrupted bores, tapped holes and atleast one center bore. One bore is sealed by a lid part. A bearing isaccommodated in the bore. Guided through the bore in the otherconnection surface is the input shaft of the gear unit.

A clutch housing for a clutch (not shown), in particular a dog clutch,is joined, in particular screw-fitted, to the gear unit with the aid ofthe further connection surface. The clutch housing is essentiallyconical and its diameter tapers in the direction of the gear unit.

The clutch housing has a flange section 10 and a connection section 11.Flange section 10 is disposed between the connection surface andconnection section 11. A sectional surface of flange section 10 parallelto the planar connection surface deviates from the circular base area ofthe connection flange. The sectional surface is flattened on two sides,so that flange section 10 is at least partially able to be brought incongruence with the connection surface.

The flattened subsection of flange section 10 has a greater wallthickness than other areas of flange section 10. The subsection extendsfrom housing 33 to connection section 11.

Flange section 10 has at least one bore, which is sealed by a sealingpart 16. Sealing part 16 is screwed to flange section 10. Sealing part16 is situated in a flattened subsection of flange section 10. The borein the flange section functions as an inspection opening. As a result,the dog clutch disposed inside the clutch housing is able to beinspected.

Connection section 11 is connected to flange section 10, preferably byscrews. Connection section 11 includes bores for a connection to aconnection flange of a motor (not shown). For transporting the gearunit, connection section 11 is sealed by a cover element 14. Bores areprovided in cover element 14 for this purpose. Cover element 14 isconnected to connection section 11 by screws 13 which are threadedthrough the bores.

In one further exemplary embodiment, which is not shown, flange section10 and connection section 11 are developed in one piece and/orintegrally formed, in particular in the form of a single cast component.

The clutch housing is optionally able to be connected to connectionsurface 39 or the further connection surface. Connection section 11 maybe used for connecting the clutch housing to a housing of a motor (notshown). For this purpose the inner diameter of the clutch housingincreases toward housing 33 in a stepped manner. The clutch housing thusincludes a step. Axial bores are situated in this step in thecircumferential direction, through which connection screws (not shown)can be guided in order to connect the clutch housing to housing 33.

The gear unit has an output shaft 21. Output shaft 21 is guided througha bore in housing 33. A ring 17 is connected to housing 33 by at leastone fastening means 18, especially using screws, which are screwed intotapped holes in housing 33. The output shaft is guided through ring 17.

A flange coupling 19 is connected to shaft 21. With the aid of anadjusting spring and/or press-fit connection, flange coupling 19 isconnected to shaft 21 in a keyed connection and/or with an interferencefit and is situated at a distance from ring 17. A retaining ring 20situated on shaft 21 fixates the flange coupling in the axial directionof shaft 21. Flange coupling 19 is provided with bores for connecting anapplication (not shown) to the gear unit.

On the side of housing 33 situated opposite flange coupling 19 there isanother uninterrupted bore in housing 33. A bearing as support foroutput shaft 21 is situated in this bore. Tapped holes 29 are disposedessentially in the circumferential direction around this bore in housing33. The bore can be sealed with the aid of a lid part 28, for whichpurpose lid part 28 is frictionally connected to housing 33. As aresult, output shaft 21 is optionally also able to be placed on theopposite side of housing 33.

On two sides of housing 33, at least two uninterrupted bores aresituated in housing 33 in each case, between the bore for the inputshaft and the bore for the output shaft. Bearings for supporting shaftsand toothed wheels disposed inside housing 33 are situated in thesebores. The bores are sealed by lid parts (8, 9, 26, 27). The lid parts(8, 9, 26, 27) are frictionally connected to housing 33 for thispurpose.

Housing 33 has a support section 32 on a short side surface. Supportsection 32 is developed as a bracket in housing 33. Bores (30, 31) forconnecting housing 33 to a support device (not shown) are developed insupport section 32.

Support section 32 defines a plane with the shaft axes of the input andoutput shaft and the shaft axis of at least one intermediate shaft (notshown). This plane is aligned horizontally, and preferably disposedessentially in parallel with the base area of housing 33.

The distance between support section 32 and the input shaft of the gearunit is smaller than the distance between support section 32 and outputshaft 21 of the gear unit.

Housing 33 includes an oil dipstick 7 and a ventilation means 6, whichare situated on the upper side of housing 33. Oil dipstick 7 is providedfor measuring the volume of a lubricant, preferably oil, inside housing33.

An oil discharge means 5 is situated on housing 33. Oil discharge means5 is disposed on a short side of housing 33. Oil discharge means 5 issituated on a side of the housing that lies across from support section32.

At least one tapped hole 4 is disposed in the surface of housing 33. Aring bolt (not shown) can be screwed into this tapped hole whentransporting the gear unit. Another bracket having a bore 12 is situatedat a right angle to support section 32, the bore being developed as atransport tab.

A shaft 40, shown in FIG. 3, of the gear unit is supported by a bearingin housing 33 of the gear unit. The bearing is situated in a continuousstepped bore in housing 33, and a retaining ring 44 situated in anannular groove in the stepped bore delimits the bearing the thedirection of the shaft axis. A spacer ring 43 is disposed between thebearing and retaining ring 44 in the direction of the shaft axis.

The radius of shaft 40 tapers in the direction of the bearing. The shaftradius has a step 48, so that the radius of a shaft section in thebearing is smaller than the radius of a shaft section set apart from thebearing. Step 48 is spaced apart from the bearing, and step 48 is spacedapart from an inner ring 46, in particular. A bushing 41 sits on shaft40, the bushing touching inner ring 46. Bushing 41 is axially situatedbetween the bearing and a toothed wheel (not shown).

The stepped bore in housing 33 is sealed by a lid part 27 on its sidefacing away from shaft 40. Lid part 27 is frictionally connected tohousing 33 for this purpose. Lid part 27 is implemented as a sheet-metalpart, in particular as a steel plate, preferably as a punched-bentcomponent. Lid part 27 is at least partially coated with plastic. Anelastomer is used as plastic. The sheet-metal part is preferablyprecisely as thick as the plastic coating up to four times as thick asthe plastic coating, preferably twice as thick as the plastic coating,the sheet-metal part in particular being approximately 1 mm thick andthe plastic coating being approximately 0.5 mm thick.

Lid part 27 has the shape of a cup and includes a base section and awall section. The wall thickness of the wall section increasesmonotonously in the direction of the base section. The inner diameter ofthe wall section increases in a stepwise manner, preferably using asingle step. An end region, facing the bearing, of the outer diameter ofthe wall section is provided with a bevel. In other words, the outerradius of the wall section is constant and in the end region decreaseslinearly towards the shaft in the axial direction.

The side of the wall section facing housing 33 is coated with plastic.The plastic thus is situated between housing 33 and the sheet-metal partof lid part 27. The side of the lid part facing away from housing 33 islikewise coated with plastic.

The stepped bore includes a step 45 and a bevel. Step 45 is provided inan axial position region of the stepped bore, which includes the bevel.

To seal the stepped bore, lid part 27 thus is pressed into the steppedbore. The lid part is pressed into the stepped bore with the aid of atool in such a way that a surface section of the outer side of lid part27 adjoins step 45 in a flush manner. Step 45 and the surface sectionthus lie in one plane.

The beveled end region of the wall of the lid part is threaded into thestepped bore and the wall of lid part 27 is elastically deformed in theprocess, so that a frictional connection is produced between lid part 27and housing 33. The plastic coating of the lid part is likewiseelastically deformed and acts as a seal with respect to housing 33.

Housing 33 has a frame section, which is shown in FIGS. 4 and 5, and acladding section. The wall thickness of the frame section is greaterthan the wall thickness of the cladding section. The frame section thusstiffens housing 33 and accommodates the bearings of the gear unit,acting as a support section, while the cladding section at leastpartially surrounds the toothed elements located inside the housing inthe form of a housing.

The frame section has a center leg section 322 and two outer legsections (321, 323). It is preferably developed in one piece. The centerleg section 322 is situated between the outer leg sections (321, 323).The outer leg sections (321, 323) are situated at a nonvanishing anglewith respect to center leg section 322 in each case. The outer legsections (321, 323) and the center leg section are preferably disposedin a U-shape.

Each the outer leg section (321, 323) has at least one annular section324, in which at least one bearing for support of the toothed elementsof the gear unit are situated. The individual annular section 324therefore is developed as one part, i.e., in one piece with theindividual outer leg section (321, 323).

A ring 170 is connected to annular section 324 in a detachable manner,preferably with the aid of screws. Ring 170 has axial bores situated inthe circumferential direction for this purpose, through which screws arefed in order to connect to tapped holes situated in annular section 324.

Ring 170 lies on a support element 172. For this purpose support element172 includes a depression developed as a concavity on its upper sidefacing ring 17. A partial ring 171 is detachably connected to supportelement 172, in particular using a screw connection. Ring 170 isinterposed between partial ring 171 and support element 172, ring 170 inparticular being fixed in place on support element 172 by partial ring171. The weight of the gear unit and the motor (not shown) connected tothe gear unit, and/or the application (not shown) connected to the gearunit is born at least partially by support element 172.

Partial ring 171 thus functions as a retaining clamp for support element172. Partial ring 171 delimits ring 170 in the axial direction. Supportelement 172 and partial ring 171 thus are connected to ring 170 in akeyed connection. The connection of support element 172 and partial ring171 to ring 170 preferably includes play.

Center leg section 323 includes a support section 320 implemented as abracket. Support section 320 is formed in one part with center legsection 323. Support section 320 has a bore 310, the bore directionbeing parallel to the normal vector of a plane defined by the framesection. Using connection means 311, guided through the bore, supportsection 320 is connected to a support element 312, preferably via ascrew connection.

Support part 321 and support element 172 are joined at least indirectlyto a foundation or a support structure, such as by a screw connection.

In another exemplary embodiment, which is not shown, housing 33 isprovided with a coat of lacquer. The coat of lacquer extends to the lidparts (8, 9, 22, 23, 26, 27, 28), lid part 2, ring 17, flange coupling19, flange section 10, and/or cover element 14.

In one further exemplary embodiment, which is not shown, the input shaftis guided through a bore in connection surface 39, so that the inputshaft projects from housing 33 on two sides of housing 33. On the sideof housing 33 facing away from the motor, an external brake isconnectable to the input shaft.

LIST OF REFERENCE NUMERALS

-   1 reinforcement surface section-   2 lid part-   3 fastening means-   4 tapped hole-   5 oil discharge means-   6 ventilation means-   7 oil dipstick-   8 lid part-   9 lid part-   10 flange section-   11 connection section-   12 bore-   13 fastening means-   14 cover element-   15 fastening means-   16 sealing part-   17 ring-   18 fastening means-   19 flange coupling-   20 retaining ring-   21 shaft-   22 lid part-   23 lid part-   24 tapped hole-   25 center bore-   26 lid part-   27 lid part-   28 lid part-   29 tapped hole-   30 bore-   31 bore-   32 support section-   33 housing-   34 surface section-   35 bore-   36 bore-   37 bore-   38 bore-   39 connection surface-   40 shaft-   41 bushing-   42 rolling element-   43 spacer ring-   44 retaining ring-   45 step-   46 inner ring-   47 outer ring-   48 step-   170 ring-   171 partial ring-   172 support element-   310 bore-   311 connection means-   312 support element-   320 support section-   321 outer leg section-   322 center leg section-   323 outer leg section-   324 annular section

What is claimed is:
 1. A bearing system, comprising: a housing component, including a stepped bore extending through the housing component; a bearing accommodated in the stepped bore of the housing; a shaft supported in the housing component by the bearing; and a lid part that seals the stepped bore and is frictionally connected to the housing component, the lid part being accommodated in the stepped bore; wherein a surface section of an exposed exterior side of the lid part is in flush alignment with a recessed step of the stepped bore.
 2. The bearing system according to claim 1, wherein the bearing includes a roller bearing.
 3. The bearing system according to claim 1, wherein the lid part seals the stepped bore with respect to an exterior of the housing component.
 4. The bearing system according to claim 1, wherein an inner diameter of the stepped bore decreases monotonously in a bore direction corresponding to an axial direction and in a direction of a shaft axis.
 5. The bearing system according to claim 4, wherein at least one step of the stepped bore includes a bevel.
 6. The bearing system according to claim 1, wherein an axial position of the surface section is an axial position of the lid part that is located farthest from the bearing.
 7. The bearing system according to claim 1, further comprising a retaining ring arranged axially between the bearing and the lid part, inside a radially oriented annular groove of the stepped bore.
 8. The bearing system according to claim 7, wherein the retaining ring is set apart from the lid part.
 9. The bearing system according to claim 7, further comprising a spacer ring arranged axially between the retaining ring and an outer ring of the bearing, the retaining ring together with the spacer ring axially delimiting the outer ring of the bearing.
 10. The bearing system according to claim 1, wherein the lid part is cup-shaped and includes a base section and a wall section, a wall thickness of the wall section increasing monotonously in a direction of the base section, an outer radius of the wall section increasing linearly toward the base section in an axial end region facing the bearing, an inner radius of the wall section increasing in a stepwise manner.
 11. The bearing system according to claim 1, wherein the lid part includes a sheet-metal part at least partially coated with a plastic coating, the plastic coating located radially between the sheet-metal part and the housing component, the plastic coating elastically deformed to seal the sheet-metal part with respect to the housing component.
 12. The bearing system according to claim 11, wherein the sheet-metal part includes a steel plate that is a punched and bent part.
 13. The bearing system according to claim 11, wherein the plastic coating includes an elastomer.
 14. The bearing system according to claim 1, wherein a radius of the shaft decreases toward the bearing in a stepwise manner, a step of the shaft is set apart from an inner ring of the bearing, a maximum outer radius of the shaft is greater than an inner radius of the inner ring, a bushing is arranged on the shaft and contacts the inner ring, an inner diameter of the bushing is greater than the inner diameter of the inner ring, an outer diameter of the bushing is smaller than the outer diameter of the inner ring, the bushing is arranged axially between a toothed wheel connected to the shaft and the inner ring, and at least one roller is arranged between the inner ring and an outer ring of the bearing. 